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v3.10.0.1

Significant Transactions (Details) |  |  |  |  | 3 Months Ended | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
May 11, 2018 USD ($) | Jan. 24, 2018 USD ($) | Oct. 05, 2017 USD ($) shares | Sep. 28, 2017 USD ($) | Sep. 30, 2018 USD ($) | Sep. 30, 2017 USD ($) | Sep. 30, 2018 USD ($) earnout_period | Sep. 30, 2017 USD ($) | May 18, 2018 USD ($) | Feb. 05, 2018 USD ($) | Dec. 31, 2017 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |
Purchases of consolidated subsidiaries, net of cash acquired |  |  |  |  |  |  | $ 252,100,000 | $ 0 |  |  |
Sales of unconsolidated affiliates and consolidated subsidiaries, net of cash sold |  |  |  |  |  |  | 0 | 1,131,000,000 |  |  |
Net (loss) gain from sale of discontinued operations, net of tax |  |  |  |  |  | $ 554,300,000 | (17,200,000) | $ 552,700,000 |  |  |
NSM Holding Co LLC |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |
Contingent consideration |  |  |  |  | $ 2,600,000 |  | 2,600,000 |  |  |  |
Contingent consideration earnout liabilities |  |  |  |  | $ 20,100,000 |  | $ 20,100,000 |  |  |  | $ 0
Healthplans.com |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |
Purchases of consolidated subsidiaries, net of cash acquired |  |  | $ 28,000,000 |  |  |  |  |  |  |  |
MediaAlpha |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |
Ownership interest (as a percent) |  |  |  |  | 62.20% |  | 62.20% |  |  |  | 64.40%
OneBeacon |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |
Sales of unconsolidated affiliates and consolidated subsidiaries, net of cash sold |  |  |  | $ 1,300,000,000 |  |  |  |  |  |  |
Net (loss) gain from sale of discontinued operations, net of tax |  |  |  | $ 554,600,000 |  |  |  |  |  |  |
NSM Insurance HoldCo, LLC |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |
Ownership interest (as a percent) | 95.00% |  |  |  |  |  |  |  |  |  |
Purchases of consolidated subsidiaries, net of cash acquired | $ 274,200,000.0 |  |  |  |  |  |  |  |  |  |
Purchase price adjustment |  |  |  |  | $ 2,100,000 |  |  |  |  |  |
Assets acquired | 495,200,000 |  |  |  |  |  |  |  |  |  |
Goodwill and intangible assets acquired | 383,000,000 |  |  |  |  |  |  |  |  |  |
Liabilities acquired | 204,600,000 |  |  |  |  |  |  |  |  |  |
Noncontrolling interest acquired | 14,400,000 |  |  |  |  |  |  |  |  |  |
Transaction costs |  |  |  |  | 6,300,000 |  |  |  |  |  |
Contingent consideration | $ 10,200,000 |  |  |  |  |  |  |  |  |  |
Number of earnout periods | earnout_period |  |  |  |  |  |  | 2 |  |  |  |
Fresh Insurance Services Group Limited |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |
Ownership interest (as a percent) |  |  |  |  |  |  |  |  | 100.00% |  |
Purchase price adjustment |  |  |  |  | $ 700,000 |  |  |  |  |  |
Assets acquired |  |  |  |  |  |  |  |  | $ 72,600,000 |  |
Goodwill and intangible assets acquired |  |  |  |  |  |  |  |  | 54,600,000 |  |
Liabilities acquired |  |  |  |  |  |  |  |  | 22,300,000 |  |
Equity method investment, aggregate cost |  |  |  |  |  |  |  |  | 49,600,000 |  |
Contingent consideration |  |  |  |  |  |  |  |  | $ 7,500,000 |  |
DavidShield |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |
Ownership interest (as a percent) |  | 50.00% |  |  | 50.00% |  | 50.00% |  |  |  | 0.00%
DavidShield & PassportCard |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |
Equity method investment, aggregate cost |  | $ 41,800,000 |  |  |  |  |  |  |  |  |
Payments to acquire business, net |  | $ 28,300,000 |  |  |  |  |  |  |  |  |
PassportCard |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |
Ownership interest (as a percent) |  | 50.00% |  |  | 50.00% |  | 50.00% |  |  |  | 50.00%
PassportCard | White Mountains |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |
Ownership interest (as a percent) |  |  |  |  | 25.00% |  | 25.00% |  |  |  |
Kudu Investment Management, LLC |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |
Ownership interest (as a percent) |  |  |  |  | 49.50% |  | 49.50% |  |  |  | 0.00%
Equity method investment, aggregate cost |  |  |  |  | $ 12,300,000 |  | $ 12,300,000 |  |  | $ 127,500,000 |
Additional funding |  |  |  |  | 63,000,000 |  | 63,000,000 |  |  | $ 125,000,000 |
Kudu Investment Management, LLC | White Mountains |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |
Additional funding |  |  |  |  | $ 31,500,000 |  | $ 31,500,000 |  |  |  |
Capital Unit, Class A | MediaAlpha |  |  |  |  |  |  |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |
Capital units, purchased | shares |  |  | 131,579 |  |  |  |  |  |  |  |
Capital units, value |  |  | $ 12,500,000 |  |  |  |  |  |  |  |

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